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| author | Christoph Hellwig <hch@lst.de> | 2017-04-05 19:21:16 +0200 |
|---|---|---|
| committer | Jens Axboe <axboe@fb.com> | 2017-04-08 11:25:38 -0600 |
| commit | f09a06a193d942a12c1a33c153388b3962222006 (patch) | |
| tree | e72cfe46da5b2cbe20a91e84c311347f081d087c /drivers/block/brd.c | |
| parent | 19372e2769179ddd154a0d6fbbdb719eb5d0af12 (diff) | |
| download | linux-f09a06a193d942a12c1a33c153388b3962222006.tar.bz2 | |
brd: remove discard support
It's just a in-driver reimplementation of writing zeroes to the pages,
which fails if the discards aren't page aligned.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Diffstat (limited to 'drivers/block/brd.c')
| -rw-r--r-- | drivers/block/brd.c | 54 |
1 files changed, 0 insertions, 54 deletions
diff --git a/drivers/block/brd.c b/drivers/block/brd.c index 3adc32a3153b..4ec84d504780 100644 --- a/drivers/block/brd.c +++ b/drivers/block/brd.c @@ -134,28 +134,6 @@ static struct page *brd_insert_page(struct brd_device *brd, sector_t sector) return page; } -static void brd_free_page(struct brd_device *brd, sector_t sector) -{ - struct page *page; - pgoff_t idx; - - spin_lock(&brd->brd_lock); - idx = sector >> PAGE_SECTORS_SHIFT; - page = radix_tree_delete(&brd->brd_pages, idx); - spin_unlock(&brd->brd_lock); - if (page) - __free_page(page); -} - -static void brd_zero_page(struct brd_device *brd, sector_t sector) -{ - struct page *page; - - page = brd_lookup_page(brd, sector); - if (page) - clear_highpage(page); -} - /* * Free all backing store pages and radix tree. This must only be called when * there are no other users of the device. @@ -212,24 +190,6 @@ static int copy_to_brd_setup(struct brd_device *brd, sector_t sector, size_t n) return 0; } -static void discard_from_brd(struct brd_device *brd, - sector_t sector, size_t n) -{ - while (n >= PAGE_SIZE) { - /* - * Don't want to actually discard pages here because - * re-allocating the pages can result in writeback - * deadlocks under heavy load. - */ - if (0) - brd_free_page(brd, sector); - else - brd_zero_page(brd, sector); - sector += PAGE_SIZE >> SECTOR_SHIFT; - n -= PAGE_SIZE; - } -} - /* * Copy n bytes from src to the brd starting at sector. Does not sleep. */ @@ -338,14 +298,6 @@ static blk_qc_t brd_make_request(struct request_queue *q, struct bio *bio) if (bio_end_sector(bio) > get_capacity(bdev->bd_disk)) goto io_error; - if (unlikely(bio_op(bio) == REQ_OP_DISCARD)) { - if (sector & ((PAGE_SIZE >> SECTOR_SHIFT) - 1) || - bio->bi_iter.bi_size & ~PAGE_MASK) - goto io_error; - discard_from_brd(brd, sector, bio->bi_iter.bi_size); - goto out; - } - bio_for_each_segment(bvec, bio, iter) { unsigned int len = bvec.bv_len; int err; @@ -357,7 +309,6 @@ static blk_qc_t brd_make_request(struct request_queue *q, struct bio *bio) sector += len >> SECTOR_SHIFT; } -out: bio_endio(bio); return BLK_QC_T_NONE; io_error: @@ -464,11 +415,6 @@ static struct brd_device *brd_alloc(int i) * is harmless) */ blk_queue_physical_block_size(brd->brd_queue, PAGE_SIZE); - - brd->brd_queue->limits.discard_granularity = PAGE_SIZE; - blk_queue_max_discard_sectors(brd->brd_queue, UINT_MAX); - brd->brd_queue->limits.discard_zeroes_data = 1; - queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, brd->brd_queue); #ifdef CONFIG_BLK_DEV_RAM_DAX queue_flag_set_unlocked(QUEUE_FLAG_DAX, brd->brd_queue); #endif |